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ML66525 Family User’s Manual
Chapter 5
Port Functions
5 - 18
5.5
Port 1 (P1)
Port 1 is an 8-bit I/O port.
Each individual bit can be specified as input or output by the port
1 mode register (P1IO).
When output is specified (corresponding bits of P1IO = “1”), the
value of the corresponding bits in the port 1 data register (P1) will be output from their
appropriate pins.
In addition to its port function, P1 is assigned a secondary function (external memory address
output).
If the secondary function is to be used, set the corresponding bits of the port 1 mode
register (P1IO) and the port 1 secondary function control register (P1SF) to “1”.
If the port is specified as an input (corresponding bits of P1IO = “0”) and the port 1 secondary
function control register (P1SF) is set to “1”, the pin inputs corresponding to those bits will be
pulled-up.
Figure 5-7 shows the configuration of the port 1 data register (P1), port 1 mode register (P1IO)
and the port 1 secondary function control register (P1SF).
0
1
7
6
54
3
2
10
0
00
0
76
5
4
3
2
1
0
0/1
P1IO7 P1IO6
P1IO3 P1IO2 P1IO1 P1IO0
P1IO
XDM14
P1SF6
P1SF
P1_7
P1_6
P1_3
P1_2
P1_1
P1_0
P1
At reset
XDM11
P1SF3
XDM10
P1SF2
P1IO5 P1IO4
P1_5
P1_4
XDM15
P1SF7
XDM13
P1SF5
XDM12
P1SF4
XDM9
P1SF1
XDM8
P1SF0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
76
5
4
3
2
1
0
0/1
At reset
(EAn = H/L)
At reset
(EAn = H/L)
Address: 0019 [H]
R/W access: R/W
Address: 0021 [H]
R/W access: R/W
Address: 0029 [H]
R/W access: R/W
Not pulled-up
P1_0 input
Primary function
P1_0 output
Address 8 output
0 (Input setting)
1 (Output setting)
Pulled-up
Secondary function
Not pulled-up
P1_1 input
Primary function
P1_1 output
Address 9 output
Pulled-up
Secondary function
Not pulled-up
P1_2 input
Primary function
P1_2 output
Address 10 output
Pulled-up
Secondary function
Not pulled-up
P1_3 input
Primary function
P1_3 output
Address 11 output
Pulled-up
Secondary function
Not pulled-up
P1_4 input
Primary function
P1_4 output
Address 12 output
Pulled-up
Secondary function
Not pulled-up
P1_5 input
Primary function
P1_5 output
Address 13 output
Pulled-up
Secondary function
Not pulled-up
P1_6 input
Primary function
P1_6 output
Address 14 output
Pulled-up
Secondary function
Not pulled-up
P1_7 input
Primary function
P1_7 output
Address 15 output
Pulled-up
Secondary function
Figure 5-7
P1, P1IO, P1SF Configuration